1% efficiency isn't going to win any awards any time soon I don't think. One commercial use might be to charge up a LED illuminator on a billboard so that it could run for a couple of hours after night fall but with solar insolation in the neighborhood of 800W/m^2 in the northern hemisphere, and the downrating due to the inability to point precisely at the Sun so maybe 5W/m^2 on a billboard is like 50 - 60W during the the solar day.